Tag Archives: photography

Thom Hogan posted some interesting ideas on his site yesterday, pertaining to the question of how we, as photographers, deal with setting exposure. Basically, in the film days, we were stuck with one ISO rating for an entire roll of film (and some of us habitually used only one type of film), so at that time, ISO was essentially a fixed value. To adjust exposure, we then had to adjust shutter speed and aperture.

Today, ISO can be varied from frame to frame, and on some cameras, there is quite a wide degree of choices available. Hogan’s idea, then, is that having a selection of finely adjustable aperture settings may not really be necessary. We pick one of our two or three preferred apertures (wide open, optimal sharpness, or maximum depth-of-field prior to diffraction), then vary the shutter speed and ISO (if needed) to get the exposure we want. The point then is that we don’t really need a whole slew of apertures to choose from.

This talk of varying the ISO brought to mind something similar that I’d been considering writing about. I got a longer lens late last year, a 300mm, which on my reduced size sensor equates to a 450mm field of view. That’s long enough to make it a significantly different animal compared to other lenses I’ve used. Furthermore, it does not have vibration reduction. On the other hand, while it’s a somewhat hefty lens, it’s weight is well within reason for hand-held use. The problem then becomes ensuring that the shutter speed doesn’t go down far enough to result in problems. In practice, I discovered that I was most comfortable keeping it around 1/800 of a second or higher. That speed allows me some leeway, meaning I can get away with sloppier shot discipline, basically. If I went down to 1/500, I would have to be very careful to hold it steady as I released the shutter, and the overall percentage of blurred shots would be higher regardless. Another thing I ran into relates to a peculiarity of my camera (a Nikon D40): higher shutter speeds sometimes seem to result in weirdness. This is sort of hard to describe, and I’ve never really been sure what the hell is going on when it happens. I suspect it has something to do with the electronic shutter that this camera uses, in that it can sometimes create some weird artifacting effects at higher shutter speeds. The anti-aliasing filter may also be a factor, or possibly the lossy compression, even though it makes no sense at all that shutter speed would interact with either of those things. I don’t honestly know what it is. However, the practical implication of it was that I realized it would work very well if the shutter speed was at 1/800 all the time, at least for hand-held shooting with this lens. Well, there’s an obvious solution to that, isn’t there? Shoot in shutter-priority mode.

The one question was what would happen when the lens opened all the way up. It’s only an f/4 lens, which is not fast enough for shady conditions or heavy cloud cover at 1/800. So I turned on AutoISO, a feature I hadn’t used on my camera in a couple of years, and which I had never ever tried in shutter priority mode. I actually wasn’t even sure it would do what I needed it to, which was to keep the camera at the base ISO of 200 until the lens was wide open, then raise the ISO upward if there wasn’t enough light. Turns out, this is exactly what it does, and it works very well. I totally recommend it, at least for Nikon bodies with this type of AutoISO, and similar non-VR long lenses. It would work with VR lenses, too, if I had some particular reason for not wanting to use the VR, such as bokeh optimization.

On other camera bodies, such as the D7000 which I will have in the not too distant future, it wouldn’t be necessary to do it this way. The D7000 has more flexible AutoISO settings. On the D40, when using AutoISO in the more typical aperture priority mode, the highest setting allowed for “minimum shutter speed” is 1/250th of a second, which is not fast enough for a lens like this. On a D7000, I am not sure what the “maximum minimum” is, but I know it’s at least 1/1000th of a second. So on a D7000, I could just leave it in aperture priority mode, set up AutoISO to allow a minimum shutter speed of 1/1000th of a second, and viola!, I’d be set to go. That camera also does not have an electronic shutter, so that particular weirdness would presumably be gone, meaning I’d have no reason to avoid very high shutter speeds.

In the mean time, though, I have accumulated quite a collection of 1/800 second shots, many of them at f/4 and weird ISO values like 520 that result from the AutoISO setting. I’ve so far only run into one instance where the camera maxed out at ISO1600. The resulting shots were about one stop underexposed, but actually looked pretty good anyway.

That, of course, leads to the other big consideration with this, which is how high can you push the ISO? There was a time when I would not have been willing to use ISO1600 on a D40. However, more recently, I’ve come to realize that the noise inherent in that setting is really not all that bad. The amount of detail lost is pretty minimal, and the noise reduction in Lightroom 3 does a pretty good job at keeping the noise under control. As long as the photo isn’t extremely underexposed, the result is a somewhat grainy looking picture, sort of like Ektachrome 400, back in the day. (Although, frankly, a D40 RAW image at ISO1600 has better color than Ektachrome 400 ever did.)

I am in the midst of trying to figure out what in the world I really need in terms of a support upgrade for my camera. A while ago, I purchased a lovely 300mm AF-S f/4 Nikkor lens, and, although the lens isn’t heavy or long enough to mandate tripod/monopod use in all circumstances, I am definitely running into some common situations where it would be helpful. One in particular is shooting out the passenger side window of the car, when I’m in the driver’s seat. Doing that hand-held quickly proved to be totally impossible at any shutter speed, due to the need to cross my left arm all the way across my body, to the point where that shoulder has virtually no leverage at all, and that’s the hand that supports the lens, in Nikon’s decidedly non-ambidextrous design. My left arm just shakes too much in that position. If I twist in the other direction, though, to shoot out the driver’s window, that works fine because now the left arm has plenty of leverage, and I can even brace my elbow on the armrest on the door. Unfortunately, there are about ten times as many good shots out the passenger side as out the driver’s side. (And if I lived in the UK, Australia, or some other country where people drive on the left, then this would not be an issue at all, because the passenger window would be on the left, not the right!)

For lack of a better immediate solution, I’ve been using an old tripod as a makeshift support, in order to alleviate the problem. It’s not stable enough to qualify as a “real” tripod support, because it’s not sturdy enough for that, but it can function as a substitute “arm”, meaning I still need to keep shutter speeds above 1/500, as I would for hand-held shots. It’s better than nothing, but I am still having problems. I am unsure of the source of the problems, but I suspect engine vibrations being magnified through the car seat, and further through the flimsy, wobbly legs of the tripod. These vibrations then cause problems for getting the lens focused correctly in some circumstances, due to the image moving enough that the focusing sensor is unable to get a perfectly accurate reading. At least, that is my theory.

I’m not sure what to do about it, because I need to be able to shoot that way, and it’s also very useful to be able to creep along in the car without having to start and stop the engine multiple times. I question whether any amount of money spent on a tripod setup would solve the problem. It might, if I was able to set it up so that one leg wasn’t braced on the passenger seat. If the springs in the passenger seat really are acting as an amplifier for the engine vibrations, then yes, a different tripod, one with more configurable and sturdy legs might actually help, so I can brace all three of them on a solid part of the car. Such a tripod would be useful for other things as well. If it doesn’t do the trick in the car, though, then I don’t think any rigid solution would work. I would need something that would directly compensate for those vibrations, such as some kind of steady-cam gimbal setup, or other type of shock-absorbing device. Maybe a great big pillow would be the thing. :) I actually did see one person using something like that with a big-assed telephoto (looked like a 400mm f/2.8) several weeks ago, while shooting from his car. I’d have to prop the pillow on top of something. Hmm. Come to think of it, what I was initially doing was using the tripod as a brace for my elbow, rather than setting it up all the way. I’d extend one leg to rest on the floor or some solid surface, then angle the top end of the tripod so I could brace my left elbow against it, thus providing the support that I couldn’t get from overextended shoulder muscles. Maybe I should just go back to doing that! However, the problem was that it was extremely clumsy, and I would often spend so much time messing around with it that whatever bird I was seeing was long gone by the time I got the tripod/elbow combination situated correctly.

I probably need a more workable solution, so I have been thinking of acquiring some kind of fairly normal tripod that would be suitable for bird shots with the 300mm f/4. It’s not a huge lens, probably comparable in size and weight to a standard 70-200 f/2.8, meaning it’s actually somewhat small compared to the big telephotos. I may add a 1.5x or 1.7x teleconverter someday, for shooting either from inside the car or out. I’m also going to want to use it for closeup shots next spring, although not from the car. I am unsure at this point if a monopod would be better for use when I’m outside of the car. Luckily, from research I’ve done so far, the main expense appears to be the head, clamp and plates, which can be interchanged between a monopod and a tripod.

The head would have to be a fairly nice ball head. I’m considering the Wimberly Sidekick to go with the head, although for the time being I’ve decided to wait and see how well a regular ball head works. The main reason for this is that I found a demo video of the Sidekick, and the thing is larger than I expected, making me think it might be overkill for my lens. Another option would be a panning ball head as opposed to a simple ball head. The panning ball head allows panning on the top part of the head, right by the clamp, which means that the tripod legs don’t have to be level in order to pan horizontally. That seems like it would be extremely convenient, however a panning head is substantially more expensive. Also, I am unsure whether that feature would be necessary if I got the Sidekick, which means I need to go watch that video again. ;) I’d also need to get a lens plate and an L-plate for the camera, both for mounting onto the ball head (or the Sidekick). I’m only considering ball heads that feature an Arca-Swiss style clamp.

For the tripod itself, I am a bit torn. I was looking hard at the Manfrotto 055XPROB, which is definitely within my price range and seems to be a pretty nice piece of equipment. I do have some reservations about the sideways capability of the center post, though. Supposedly, this can create stability issues, and there’s also the question of whether I would even need that sideways leaning feature. Manfrotto has a similar tripod with just a traditional up-and-down center post, the 055XB, but, unfortunately, the retailer I was planning on using doesn’t carry that model! That would be a minor quibble, except there’s enough variation in prices between retailers that having to go elsewhere would (apparently) cost me an additional $20, even with the simpler design! I may also need a shorter center column. Those can be had for about $30, if I remember right.

For the legs, if I manage to find the Manfrotto 055XB carried by someone who’s asking a good price, it should come to roughly $155. That’s about $20 cheaper than some places are asking. Then the ball head would be either $356 with the standard clamp or $515 (!) with the panning clamp. The plates could also be obtained from Really Right Stuff. An L-plate for the camera would come to $125, and a plate for the lens would be $55. If I wanted to skimp a bit, I could initially skip the L-plate and just get the one for the lens….actually, since I’m thinking about upgrading camera bodies, I could save some money and just wait to get the L-plate for the new body. In fact, I could skip all of this plate stuff for now and just get a ball head with a platform (no clamp), then add the panning clamp later. That’s one nice feature of the Really Right Stuff heads–the clamps and platforms are interchangeable.

However, assuming I go with the regular style clamp ball head, I’m looking at $566, including the tripod and a plate for the lens.

That’s pretty steep, considering just a few hours ago I blew more than that on car repairs. :(

There are some particularly interesting tidbits of information in Part 1. For these, he’s talking about changes he’s made compared to the default camera settings:

Moving focus activation from the shutter button to the AE-L/AF-L button on the back of the camera.

This is very cool. Not only was I not aware that the D7000 had this capability, but it’s one of the key features I came up with a couple months ago when I was questioning whether a D300s body would be worth the extra few hundred dollars. Having autofocus separate from the shutter release button would come in very handy on landscapes and scenics—it means that, basically, the camera is in manual focus unless I press the button. The primary drawback of the D7000, with respect to my needs, is therefore eliminated. (I should also check and see if my D40 can do this. Who knows! Maybe I’ve been a dumbass all this time, wearing out the focus switch on the lens to accomplish the same thing!)

Changing the release priority from focus to shutter. In its default mode, the D7000 will allow the shutter to release only if something is in perfect focus.

Another little bit of trivia which may turn out to be very handy at some point.

Then, continuing on to part 2:

My experiments indicated that matrix metering tends to be overly influenced by heavy shadows, with the result that skies and clouds are overexposed.

This is unfortunate. I have the same problem with my D40. In fact, if I had to make a prioritized list of stuff I don’t like about the D40, this problem would be either #1 or #2 (with poor focusing performance being the other). However, it is possible that the D7000 does not exhibit the problem to the same degree as the D40, and the review also goes on to discuss ways to work around it. In practice, it doesn’t seem to be an insurmountable problem, but I’ll have to remember to keep an eye on other reviews to see if other people notice it as well.

One commenter also discusses the metering issue:

[T]he one thing I always hated about Nikon still remains, then: matrix-metering that doesn’t understand simple 1+2 or 1+4 sky:landscape compositions. It was for that reason I *always* shot my D200 in manual+spot mode.

I know there’ve been many Nikons passed under the bridge since then, so I’m surprised it’s still an issue.

So am I.

There’s more, of course. He’s particularly complimentary regarding the responsiveness of the camera.

It’s a good review, well worth reading for anyone interested in a D7000 body, and substantially more readable than, say, a Dpreview.com review. ;)

Who else would even think to do something like that? And it’s a genuinely interesting comparison, too, not just because I am a D40 user, but for a more substantive and technical reason: If you do the math, it turns out that the individual photosites on the D40 and the D3 sensors are pretty close to the same size. That means what you’re seeing in these photos, if you compare strictly the D40 and D3 shots, is a pretty good comparison of how Nikon improved its sensor noise handling technology between those two generations of cameras. It’s really a striking illustration of how dramatic the improvement was, at ISO1600 and beyond.

It’s also a pretty good exemplar of how well the D40 handles itself at ISO 400 or even 800. (The colors do tend to be a little duller on the D40 shots, but I’m guessing that’s because the D3 and D3100 have Nikon’s Picture Control feature, while the D40 doesn’t. That would mean the D40 is using different JPG conversion parameters, so it’s not surprising that the colors look different.) The D40 ISO800 shot looks almost as good as the base ISO200 shot. This matches my own experience: I’ve found that ISO 400 is quite usable when an extra stop is needed for wildlife or what-have-you, and I can even use ISO800 to get acceptable results if I need to. Yes, there is more noise at that sensitivity, but as Rockwell says, it’s not just about the noise. Noise can be dealt with. The level of detail retained in the photo is the key issue, and it appears to be roughly the same at ISO400 and 800, with ISO200 having a bit of an edge. This supports my belief that, in terms of bumping up the ISO sensitivity, the D40 is the best of its generation of cameras (namely the D100, D70, and D50). I would also guess it handles those speeds better than its immediate successors (namely the D40x and D60…not so sure about the D3000, though).

Pro-D40 ranting aside, the other interesting thing about that page is how clearly it demonstrates that the D3100 is a step up from the earlier generation of camera. It’s only at ISO6400 that the D3 begins to look significantly better than the D3100. Compare this to the D40, which is essentially crap at ISO3200–in fact, it doesn’t actually have a proper ISO3200 setting, it’s actually “HI 1”, and it can’t shoot at ISO6400 at all.

Basically it has a search form on it where you can choose a lens, choose a camera, choose some other specifications like focal length range or aperture range, and it’ll search its database of photos for ones that match those criteria. So, for instance, I picked the Nikon 16-85mm VR, and the Nikon D40….and received zero matches. :) However, each menu also has an “any” option, so when replacing the D40 with “any,” I got many more results. Then you can look at the specs for each photo match or click on a link to view a full resolution version and “pixel peep.”

The problem is that most of these pics appear to be hosted on Flickr. Many, many Flickr users have their original size photos hidden, so when you click on that link it just says “oops, private page.” All you are allowed to see, in many cases, is the 500 pixel wide “medium” version. That seems like a pretty major flaw. You can’t tell very much about lens quality by looking at a 500 pixel image. Even the quality of the bokeh will look different when the resolution is reduced that much.

[This was originally going to be a quick response to a question posed in a Flickr discussion thread (“Over exposed skies on D60“), but I found myself typing more and more, so I figured it would make a good blog post.]

The meters on the entry level Nikon DSLRs (and the D80, if I understand correctly) are tuned to ensure that darker areas aren’t underexposed, but this often leads to a problem: The sky, or other bright area, ends up “blown out.” There are various ways to alleviate this, none of them ideal.

Ideally, one could simply use a graduated neutral density filter, but such a filter has a built-in, natural limitation, namely that it works best when you can ensure that the sky is in the top half and the landscape is in the bottom. If the division between the two is uneven, as it is in many photos, then it’s not going to be as helpful. There is also a problem when the front element of the lens rotates, as it does on Nikon’s 18-55mm kit lenses.

Luckily, there are other methods:

1) Using matrix metering with the exposure compensation feature. Take a shot, check the histogram or highlight display to see how badly the sky is blown out, adjust exposure compensation accordingly, then try another shot. Be sure to center the frame in the same spot as the first time, so the meter receives the same input both times. In extreme cases, I’ve had to adjust exposure compensation multiple times to get it “right.” A single value is not going to work for every situation. I’ve used compensations varying from -0.3 to -2.7, although -0.7 to -1.7 seem to be the most common. The greater the compensation, the more contrast there’ll be in the final picture. At an extreme value like -2.7, the result is going to be questionable at best. With experience you can take a guess at your compensation value on that first shot, and save yourself some time.

2) Another thing to try is putting the lens on manual focus and setting “exposure lock” to “ON”. (Ironically, it’s possible this method never would have occurred to me if autofocus hadn’t been broken on my kit lens.) Expose an area right on the edge of the sky, hold the shutter button half down to lock the exposure, recompose, and shoot. With the lens on manual focus, you can focus at whatever point in that sequence is most convenient. Then check your exposure just like in (1). Thanks to metering the edge of the sky, the chances are much greater that your exposure will be correct on the first shot, but even if it’s not, you’ll need much less adjustment.

This exposure lock method is easier with autofocus off. With autofocus on, you’ll soon find yourself in a situation where your focus point, your metering point, and the center of your composition are three different spots, and it gets pretty hairy trying to handle all of that (especially if you prefer the left eye like I do, meaning the AE/AF-lock button is mashed right up against your face!). In fact, wanting to avoid this situation was the main reason I decided to learn the next method:

3) Just use manual exposure mode. If you want autofocus on, this will often work better than (2). Adjust the shutter speed and aperture explicitly, then check your results as in the other two methods. I find that manual exposure works best in the winter. In the summer, the presence of green vegetation increases the possible variability of the lighting, and adding a polarizer adds yet another variable, so eventually it gets to be too much to keep track of. That’s why I’ve never entirely given up on methods (1) or (2). However, in situations where the lighting is pretty consistent, this is actually the easiest method.

Wondering what values to start with? That’s not really all that hard. There’s an old heuristic called the “Sunny f/16 Rule” and it goes like this: On a sunny day, you can set your aperture to f/16, your shutter speed to the reciprocal of your ISO value, and the chances are good that this exposure will be right. Whether it turns out exactly right depends on various things, but it’s always a good starting point. You probably don’t want to use f/16, so when you move the aperture down, count how many steps you go, then count that many steps faster on your shutter speed. On a Nikon D40 at base ISO 200, then, the starting point would be f/16 at 1/200 second. But I’d rather shoot at f/8, which is two stops down (or six clicks on the wheel), so then I’d bump up the shutter speed two stops (six clicks) to 1/400 second. Easy! :)

4) I’ve tried abandoning matrix metering in favor of center-weighted, but gave that up after a couple of weeks because I found it was leading to even more tedious adjustment and fiddling than matrix metering. Instead of just needing negative exposure compensations, I now found many of them ending up on the positive side, making the whole process into a complete bother. How I managed to survive for years shooting film with a center-weighted camera is beyond me. :)

5) There’s always HDR, which I haven’t tried, mainly because it’s a computer intensive method (the less time I can spend in front of the computer, the better!). I will hazard a guess that this is the most complicated method of all. Or perhaps the method requiring the most art. :) I’ve seen plenty of cheesy, tasteless HDR compositions. A few of them look really superb, though (whether done with a realist aesthetic or not), and in extreme situations, I am sure that this is the only way to really get the shot.

6) I have found that a circular polarizer can sometimes help. When it does, it’s because the polarizer is actually darkening the sky, thus reducing the overall contrast. But that means it works less well when that darkening effect is minimized, such as in the late afternoon or early morning, or when the air is hazy. Unfortunately, these are precisely the times when the contrast problem is likely to be greater.

7) Whichever of the above methods you use, be sure you are shooting RAW. It has better dynamic range, and overexposed areas can often be “recovered” in post processing. That doesn’t work with JPG images.

So that’s basically it, there’s no “easy” way out, strictly speaking, unless you want to get a camera body that has some type of in-camera dynamic range expansion. I’ve seen some samples of this from the Pentax K-7, and they look somewhat fakey to me, not as good as a high-quality, manually done HDR image can. (Perhaps this is a matter of setting parameters in the camera, though.)

I saw a group of four Whooping Cranes yesterday. What a surprise! I could hardly believe my luck.

I was on a photo excursion/hike at Horicon National Wildlife Refuge, had been outside for the better part of an hour already, and was nearing the end of the trail. I was a little tired (I am so out of shape it’s ridiculous) and I came really close to walking right by them without even realizing what they were! Horicon Marsh is heavily populated by Great Egrets, which are very beautiful, large, white birds, but they are so common that I’ve gotten kind of blasé about them sometimes. So when I saw four large white birds over a ways along the trail, that’s what I initially assumed they were, and went about my business shooting wide angle landscape shots (I actually have a couple of shots with small, white specks, i.e. Whooping Cranes, in the background, heheheh). I didn’t even have the right lens on my camera to look at them—for the day, I had decided to use the D40 kit lens, complete with broken autofocus. However, I was near the end of the hike, and was feeling like my kit lens project had been a success, so I decided I would take a break from deep landscape shots and grab a shot of those four big white birds over there, even though I knew they were too far away to make a good photo.

It hadn’t occured to me that Great Egrets tend to be pretty solitary, so what were four of them doing together? And weren’t they a little bit too large to be Great Egrets? And where was all the cool neck flexion and posture stuff you usually see with an egret? And what was the deal with the black on the wings? That didn’t seem right. And yet, the truth of what I was seeing still didn’t dawn on me, until I had switched lenses, zoomed in on them and realized they couldn’t possibly be egrets. My next thought was White Pelicans, but that only flashed through my mind for a moment—they were not bulky enough, and didn’t have the gigantic beak apparatus that pelicans have, so that idea was obviously wrong. I also saw a quite distinctive dark facial marking. This is actually reddish, but from that distance, on a cloudy day and through my small viewfinder, it just looked an indistinct “dark” color, compared to the surrounding white. Still, though, it was a clear indicator of what I was looking at, as was the way they walked, very much like a Sandhill Crane.

You have to understand, when one doesn’t expect to ever see a Whooping Crane ever, having not just one but four of them right there in plain sight is a little difficult to accept. So as I snapped excitedly away, knowing full well that the pictures would be mediocre at best (and not caring one bit!), my mind still hadn’t quite opened up to the idea that me, a basic birding nobody, had any business seeing such rare birds. Who the hell did I think I was, anyway? However, when they began to dance…well at that point there was no denying it, and I just about started to do a little dance myself! ;)

Regrettably, by the time they started dancing, they had moved behind some reeds, so I couldn’t see that part very well. I took a few shots of it anyway, just for documentation purposes. They didn’t turn out very well. The main body of shots was quite usable, if somewhat mediocre as I expected. I was too far away, with a lens renowned for mediocrity at its mere 200mm maximum length, and with only a six megapixel camera. But given these limitations, the photos turned out ok. I may even crop one of them to use as a banner photo for this blog! I haven’t decided yet. ;)

All in all, it was an exceptionally thrilling sighting! I just hope it doesn’t turn out to be the only time in my life I ever see these birds. They really are exceptionally beautiful. Here’s one sample shot, which honestly doesn’t do them justice:

I have actually gone a bit nuts by posting a set of sixteen shots on my Flickr stream. They are the ones that I felt were at least moderately acceptable. Normally I’d want to focus more on quality of the photo, but with birds this rare, I figure who cares. So here is the whole freakin’ set. Enjoy! :)

I’ll almost certainly be back there next weekend, to see if I can spy them again. :)

Update: I just realized that I can post a link to a full-blown slideshow of the whole set. Why bother with all the tedious clicking around when you can just view the entire set, in large size? ;)

Finally, I have to add that I went back to that same spot on October 10th and saw the same four birds again! Like the first time, it was pretty surprising, and very nice to see. This time, the weather was sunny, and the sunlight on their pure, white feathers was really amazing. The only thing, though, is that this time they were even farther away than the first time, so the photos from that afternoon were only useful for identification and documentation purposes.